to PROMISE (one) the MOON
作不切實際、輕率的許諾

We would love to believe everything other people tell us, but experience teaches us that sometimes other people promise things that they cannot ever deliver. In some cases, they mean well and have good intentions, but they overestimate their ability to fulfill their promises. In other cases, they purposely deceive us in order to gain some advantage.

In the end, however, it is actions and deeds, not promises or excuses, that have any true meaning. After all, if someone promised to give you the moon as a present, would you believe them? Of course not! Therefore, when we suspect that someone is promising things that they cannot possibly fulfill, we say that they are "promising the moon."

source from: student post

Ummmm.....i would believe Kat if she promised to give me the moon as a present....hei hei

I would believe her toooooo Green, but I do not have any idea what I would do with the moon.

EastCoast

Green, when someone promises you a moon as a present, tell him that you'd rather like a star, and that a sparkling diamond is good for a replacement if a star is too high to reach.

Im afraid he would dump me in no time after i raised that request....ha ha

I am sure he would try Green, but where would you put it if he could give it to you. ........